Cap for armor-piercing projectiles



Mar. 20,1923. R. A. HADFIELD ELAL. CAF FOR ARMOR PVIERCINGPR01EGI'ILEHS.

min Dec. 1s, ma.

2 SHE pricey Mai. 20, 1923. R. A. HADFIELD ET AL. P

cAP FOUR ARMyo PIERCING rfRoJfcTlLEs.

z'sHEETs-snner 2."

FILED DEC. 18,1918.

' zum waff, wdf y Patented ar. 2, i923.

ROBERT ABBOTT il GEORGE Mex JACK, F SEEE ENGLAND? CAE FOB OE-PIEG'FROJECTHES.

- Application med December le, 191e. v Serial No. 267,276..

.To all whom it my concern.'

Be it known that we Sir Ronnu'r Henrmnn, baronet, F. S., and ALEXANDERGroen Menara Jaen, subjects of the e King of Great Britain and ireland,residing, respectively, at the city of Westminster. England andSheiiield, in the county ot' York, ngland, vhave invented improve mentsin or Relating to Caps for Armoric Piercing Frojectiles, of which thefollowing is a specication.

ylhis invention has reference to the caps tted to armor piercingprojectiles with the object of enabling such projectile to success- 15fullliy perforate hard faced armor plates.

eretofore such a cap has been providedl with a smooth conical, conoidal,rounded, that isl to say convex, or concave front end portion, or with acentrally arranged rounded or dat end portion, projecting forwardly fromthe remalning portion of the cap, for

, attacking the plate and weakening it before v the point of theprojectile reaches it, so as to facilitate perforation of the plate bythe pro'ectile.

ith all these constructions of cap, the smooth front end portion ofthecap on impact against a hard faced plate, compresses' the surfaceportion of the plate and forms a sin le indentation 'or depressiontherein,

an whilst weakening the' plate to some ex` tent, compresses the portionof the metal di rectly struck. Furthermore, there is a liability of thecapped projectile when striking on an armor late obliquely, especiallyat `a large angle, sipping along the surfaceof the plate and failing toindent the plate in such a manner as to` centre it and enable the capand projectile to successfull attack the 40 plate in such a manner as toena le the projectile to periorate the plate.

Now the present invention has for its object to enable the cap of acapped armor piercing projectile on impact against a hard faced armorplate, to engage, dig into and damage the plate, either when strikingnormally, or obliquely, and in, the latter case, even at a large anagle,in a better manner than heretofore an so as to shatter, break 5 up ordisintegratethe hard ltace of the plate 'so as to form, inefect,'a-roughened,serrated,

in a more eective manner than heretofore usual, in order the better toensure perforation of the plate by the projectile in the deslred manner.1

For this purpose, the front end portion of the cap instead of being madewith a smooth surface as heretofore, is provided with a number ofcutting or indenting points, blades, edges, ridges or equivalent,

ribbed or irregular surface adapted, on impact against the hardenedsurface of an arrnor plate, to diglinto such surface at a number ofpoints so as to scarify or break up and thus eectually to disintegratethe portion of the hard surface of the plate struck by. the cap and thusbetter to prepare the remainder of the plate behind such surface forbeing more easily and successfully perforated by the projectile thanheretofore.

The roughened, serrated, ribbed orirrcgular surface `of the cap can` bevariously formed; Thus, it may consist of a comparatively large numberof small projections or teeth of pyramidal, conical or conoidal shape, wor in the form, of knife blades or edges and be arranged' in variousways. 0r it may consist of a comparatively -small number of suchprojections or teeth, for instance of a few short projections or teethof pyramidal form. The projections, teeth, ribs -or rib may be ofpointed shape, or-` of truncated shape, or some may be pointed andothers truncated. j

In the accompanying illustrative drawings, Fig. 1 shows in' centrallongitudinal section, part of a ca 'fitted to an armor piercingprojectile an having a rou hened surface according to the invention. t ecap and projectile being shown provided with a hollow point or airdeector. Fig. 2 is a developed view showing part of the roughenedsurface of the cap shown in Fig. 1. Figs. 3. 5, 7 and 10 are similarviews to Fig. l and Figs. 4, 6, 8, and 9, are similar views t0 Fig. 2,showing modified constructions.

Referring to Figs. 1 and 2, a is a cap fitted to a projectile b andprovided with a hollow oint or air dei-lector c, part ,only of which 1sshown. The front end portion of the cap 100 is provided with a`roughened surface comosed, in this example, of a comparatively argenumber of projections d of pyramidal shape arranged to form a 'series ofparallel grooves and pro'ections.

In Figs. 3 an 4, the projections d1 are of conical shape and in Fi s. 5and 6 the projections d2 are of conoi al shape.

In Figs. 7 and 8, the forward end of the cap a is provided with acomparatively small number of projections d5, Ishown as of pyramidalform, arranged in circular rows and staggered with relation to oneanother.

The projections may be pointed, as shown at d, d1, d2, d5 in Fi s. 1 to8 inclusive or they may be of truncate shape, as shown at d* in Figs. 3and 5, or both forms may be used on the same cap.

Where segmental ribs are used, they may be staggeredv as shown at d8 inFig. 9. Also, the free ends of such ribs may be sharp as shown at d1 inFig. 9, or truncated, as shown at d* in Fig. 10, so as to provide alarger number of cutting edges.

The roughened surfaces may be produced by knurling, moulding, stamping,forging, cutting or otherwise, according to their nature.

Such a cap is or may advantageously be f hardened, or hardened andtempered, in any suitable or known way, so as to impart desiredqualities thereto and so .as to produce a hardened, and, it may be,tempered, rou hened, serrated or irregular front end sur ace thereon.

As will be readily understood, a cap constructed as described and shownwill, upon striking an armor plate, act to disintegrate or break up thehard surface of the plate and facilitate the perforation of the late bythe projectile to which the cap is xed.

lThe invention can be applied to caps of various shapes such as thosehereinbefore indicated, or other shapes, and over any desired proportionof the front end portion thereo What we claim is 1. For an armorpiercing projectile having a hardened and tempered ogival shaped polntedhead, a cap, the rear end ortion of which is recessed and adapted to tover and be secured to the ogival shaped head of the projectile and thefront end portion of which is provided with aplurality of independenthardened projections adapted to dig into and scarify the surface of ahard faced armor plate and each extending only a comparatively shortdistance around the circumference of the cap.

2. For an armor piercing projectile having a hardened and temperedogival shaped pointed head, a cap, of substantially o val shapeexternally, the rear'end portion o the cap being recessed and adapted tofit overv and be secured to the ogival shaped head of the projectile andthe front end portion of the cap being provided with a plurality offorwardly extending hardened projecting portions arranged at varyingdistances from the extreme front end of th cap and each extending only acomparatively short distance around the circumference of the cap.

3. For an armor piercing projectile having a hardened and temperedogival s haped pointed head, a cap the rear end portion of which isrecessed and adapted to fit over and be secured to the ogival shapedhead of the rojectile and the front end portion of whic is provided witha plurality of forwardly projecting hardened portions located atdifferent distances from the extreme front end of the cap and inclinedat different angles to the longitudinal axis of the cap.

4. For an armor piercing projectile havin a hardened and tempered ogivals haped pointed head, a cap Athe rear end portlon of which is recessedand adapted to fit over and -be secured to the o 'val shaped head of theprojectile and the ont end portion of which is provided with a pluralityof hardened projectionsflocated at varying distances from the extremefront end of the cap, each projection being of gradually decreasingcross-sectional area towardlts free end and having a base that extendsonly a comparatively short distance around the circumference of the cap.

5. For an armor piercing projectile having a hardened and tempered capthe rear end of which 'is recessed and adapted to ft over and be securedto the pointed head of the rojectile and the front end portion of w ichis of convex shape and provided with a plurality of hardened projectionsof tapering shape located at varying distances from the extreme frontend of the cap, each projection having a base that extends only acomparatively short distance around the circumference of the cap and asharp forward end. 6. For an armor piercing projectile, a cap the frontend portion of which is provided with a plurality of projectionsarranged in parallel rows.

7. For an armor piercing projectile, a cap the front end portion ofwhich is provided with a plurality of projections each of pointed shapeand extending only partly around the circumference of the cap.

8. For an armor piercing projectile, a cap the front end portion ofwhich is provided with a number of projections arranged in staggeredrelationship.

9. For an armor piercin projectile, a cap the front end portion o whichis provided with a number ofl projections arranged in staggeredrelationship and of pointed shape. v

IDI

10. For an armor piercing projectile, a 'vided with a large number ofclosely pitched ca. the front end portion of which is proprojections ofpointed shapea vi ed with a plurality of projections lof 13. For anarmor piercmg projectile, a pyramidal shape. cap the front end portionof which is ro- 5 11. For an armor piercing projectile, a vided withalarge number of closely pitc ed l5 ca the front end portion of which isproprojections of pyramidal shape.

vi ed with a large number of closely Signed at London, England, thiseightpitched projectior'xs.l eenth day of November, 1918. 12. For anarmor piercing projectile, a, ROBERT ABBOTT HADFlELD. 10 cap the frontend portion of which is pro- ALEXANDER GEORGE MKENZ|E JACK

